Yes you will need everything again. But you can make it easier by getting organised. Keep docs ready to be printed on your computer, then photos, Kor Ror 2, Bank and off you go.
Also use only the 400k in the bank, don't even try the income option, some offices won't do it anyway.
I did 7 extensions, took about one day for each, needed also an extra hour or two to get the stamp. But when the LTR came, it was a no brainer, just got it.